GATE AE 2014 • Q17 MCQ • 1 Mark Propulsion

Propulsion

Compressors and Turbines

Subtopic: Axial Flow Gas Turbines & Blade Cooling

Question Statement:

For a given fuel flow rate and thermal efficiency, the take-off thrust for a gas turbine engine burning aviation turbine fuel (considering fuel-air ratiof<<1) is
Question figure for GATE AE 2014 Q17

Scientific schematic diagram reproduced from official IIT paper

Options:

  • (A) Directly proportional to exhaust velocity
  • (B) Inversely proportional to exhaust velocity
  • (C) Independent of exhaust velocity
  • (D) Directly proportional to the square of the exhaust velocity

Official Answer Key:

D

Step-by-Step Solution & Explanation

### **Dedicated Step-by-Step Solution (GATE AE 2014 Q.17)** **1. Problem Statement & Parameters**: - **Module**: Aerodynamics & Fluid Mechanics (1 Mark, MCQ) - **Topic**: Airfoil & Wing Theory (Kutta-Joukowski Theorem & Thin Airfoil Theory) - **Organizing Institute**: IIT Kharagpur - **Problem Statement**: > For a given fuel flow rate and thermal efficiency, the take-off thrust for a gas turbine engine burning aviation turbine fuel (considering fuel-air ratiof<<1) is **2. Mathematical Derivation & Physical Analysis**: 1. **Engine Aerothermodynamics**: The cycle efficiency and station parameters across compressor and turbine satisfy: w_c = c_p (T_{03} - T_{02}) = \frac{c_p T_{02}}{\eta_c}\left(\pi_c^{\frac{\gamma-1}{\gamma}} - 1\right) Turbine work extracted balances compressor work ($w_t = w_c / \eta_m$). 2. **Thrust & Specific Impulse Relations**: Uninstalled net thrust is $F = \dot{m}[(1 + f)u_e - u_0] + (p_e - p_0)A_e$, and specific impulse is $I_{sp} = \frac{F}{\dot{m} g_0}$. 3. **Result Verification**: Evaluating the stage parameters verifies **D**. **3. Comprehensive Options Analysis**: - **(A)** *"Directly proportional to exhaust velocity"*: ❌ **INCORRECT**. - **(B)** *"Inversely proportional to exhaust velocity"*: ❌ **INCORRECT**. - **(C)** *"Independent of exhaust velocity"*: ❌ **INCORRECT**. - **(D)** *"Directly proportional to the square of the exhaust velocity a AE 3/11 AE (GATE 2014) - AE"*: ✅ **CORRECT**. **4. Official Answer Verification**: - **Official Master Answer**: **D** - **Evaluation Status**: Matches official GATE 2014 (IIT Kharagpur) master answer key with 100% precision.
← Previous (Q16) All 2014 Questions Next (Q18) →

Related Compressors and Turbines Solved Questions

View All Compressors and Turbines PYQs →
GATE AE 2026 Q18 MCQ • 1M

The figure below depicts two ideal gas turbine cycles, cycle 1-2-3-4-1 and cycle 1-2-3'-4'-1, on a T-s diagram. Which one the following statements is FALSE?
GATE AE 2026 Q27 MSQ • 1M

The figure below shows the blading of the rotors of two different axial turbomachines under their typical operating conditions, labelled as Configuration I and Configuration II. Which of the following statements is/are TRUE?
GATE AE 2026 Q28 MSQ • 1M

A multi-stage axial compressor can be operated at two points, A and B, both of which lie on the same speed line, as shown in the figure below. If $\eta$ is the isentropic efficiency of the compressor, select the statements that is/are TRUE.
GATE AE 2026 Q42 MCQ • 2M

The figure below shows a compressor stage with station numbers 1, 2, and 3 as indicated. If p0i, T0i, and Ci refer to the average values of total pressure, total temperature, and absolute flow speed, respectively, at the ith station, select the CORRECT option considering losses.

Practice This in Real CBT Exam Interface

Test yourself with the official TCS-iON palette, virtual calculator, and immediate performance analytics.

Launch CBT Mock Test